KR20050059625A - Tension mask frame assembly for color cathode tay tube - Google Patents

Abstract

An object of the present invention is to provide a tension mask frame assembly for a color cathode ray tube having a reduced effect of thermal drift. To achieve the above object, the present invention provides a tension mask, which is spaced at a predetermined interval, and in which the tension mask is seated. First and second supporting members including first and second supporting surfaces and first and second supporting members spaced apart from each other at predetermined intervals and connecting the first and second supporting members. A first member and a second rigid member disposed between the first and second support members, the first and second rigid members supporting the first and second support members and being close to the longitudinal center of the first supporting surface. The longitudinal radius of curvature of the first ground portion is greater than or equal to the longitudinal radius of curvature of the first ground portion that is far from the center, and is the longitudinal radius of curvature of the second ground portion that is close to the longitudinal center of the second ground surface. this And a tension mask frame assembly for a color cathode ray tube, characterized in that it is greater than or equal to the longitudinal radius of curvature of the second support surface portion away from the center.

Description

Tension mask frame assembly for color cathode tay tube}

The present invention relates to a mask frame assembly for a color cathode ray tube, and more particularly to a tension mask frame assembly for a color cathode ray tube having a support surface having a plurality of radii of curvature.

A typical color cathode ray tube excites an image by landing three electron beams emitted from an electron gun onto red, green, and blue phosphors of a fluorescent film formed on the screen surface of a panel through an electron beam through hole of a mask having a color screening function. To form.

In the color cathode ray tube forming an image as described above, a mask having a color selection function is roughly divided into a dot mask employed in a computer monitor and a slot mask (also called a slit mask) used in a television or the like. Tension mask, which is one of the slot masks, is supported so that tension is applied by a frame in consideration of a flat screen surface in order to compensate for image distortion and widen a viewing angle of a screen.

On the other hand, the tension mask frame assembly in which the mask is supported so that the frame and the tension is applied by the frame, is mounted inside the panel of the color cathode ray tube, Figure 1 shows an example of such a color cathode ray tube (10).

Referring to the drawings, the color cathode ray tube 10 includes a panel 13 having a planar screen surface 12 on which a fluorescent film 11 is formed, and a tension mask frame assembly 20 suspended on an inner surface of the panel 13. ), A funnel 15 enclosed with the panel 13 and an electron gun 16 enclosed in the neck portion 14, and a deflection yoke 17 provided in the cone portion of the funnel 15. .

As shown in FIG. 2, the tension mask frame assembly 20 includes a tension mask 22 having a plurality of long slots 21 formed therein, and supporting members 23 supporting edges of the tension mask 22. And rigid members 24 supporting end portions of the supporting members 23 so that tension is applied to the tension mask 22. The support surface of the support members 23 on which the tension mask 22 is mounted has one radius of curvature in the longitudinal direction.

However, in the color cathode ray tube 10, thermal drift of the tension mask 22 occurs due to various causes. This thermal drift is mainly due to the thermal expansion of the tension mask 22, saddle doming and Poisson expansion. Since thermal drift due to Poisson expansion is generally small enough to be negligible, thermal drift is determined by thermal expansion and saddle domming of the tension mask 22. 3 is a graph showing the thermal drift in the tension mask 22 according to the prior art. The horizontal axis of the graph represents the length x in the horizontal direction with respect to the center of the tension mask 22, and the vertical axis represents the thermal drift. As shown, the thermal drift due to thermal expansion increases linearly with the position x away from the center. On the other hand, thermal drift by saddle domining has a parabolic shape that is convex upward. Referring to the figure, the sum of the thermal drifts generated by saddle domming and thermal expansion is converted from a positive value to a negative value at a position x about 250 mm from the center. In particular, as it approaches the horizontal axis end of the tension mask 22, the thermal drift has a negative value. Such thermal drift of the tension mask 22 causes a change in the landing of the electron beam, resulting in a problem that the performance of the color cathode ray tube 10 is degraded.

An object of the present invention is to provide a tension mask frame assembly for a color cathode ray tube having a support surface having a plurality of radii of curvature.

In order to achieve the above and other objects, the present invention provides a tension mask, a first and a second support member including first and second support surfaces spaced at predetermined intervals and on which the tension mask is seated. It is disposed between the first and second support members at predetermined intervals, and disposed between the first and second connection members connecting the first and second support members, and between the first and second support members. A first support member having first and second rigid members for supporting the first and second support members, wherein the longitudinal radius of curvature of the first support ground portion close to the longitudinal center of the first support ground is far from the center; The radius of curvature of the second ground surface portion that is greater than or equal to the longitudinal radius of curvature of the face portion and close to the longitudinal center of the second ground surface is greater than the longitudinal radius of curvature of the second ground portion that is remote from the center. Or like Provides a color cathode-ray tubes tension mask frame assembly.

In the present invention, preferably, in the tension mask frame assembly for the color cathode ray tube, the longitudinal radius of curvature of the first and second supporting surfaces may be symmetric with respect to the centers, respectively.

In the present invention, preferably, in the tension mask frame assembly for the color cathode ray tube, the eleventh and twelfth inflection points are respectively positioned on the first supporting ground so as to be symmetrical to the longitudinal center of the first supporting ground, The support surface between the inflection point and the twelfth inflection point has a longitudinal radius of curvature R11 and between the inflection points adjacent to the longitudinal ends of the first support ground and the longitudinal ends of the first support ground, respectively. The support surfaces of have a longitudinal radius of curvature R12 and may be R11 ≧ R12.

In the present invention, preferably, in the tension mask frame assembly for the color cathode ray tube, the twenty-first and twenty-second inflection points are respectively positioned on the second supporting surface so as to be symmetrical to the longitudinal center of the second supporting surface, The support surface between the inflection point and the twenty-second inflection point has a longitudinal radius of curvature R21 and between the inflection points adjacent to the longitudinal ends of the second support ground and the longitudinal ends of the second support ground, respectively. The support surfaces of have a longitudinal radius of curvature R22 and may be R21 ≧ R22.

Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Referring to Figure 4, there is shown a tension mask frame assembly 100 for a color cathode ray tube according to an embodiment of the present invention.

As shown, the tension mask frame assembly 100 for the color cathode ray tube includes a tension mask 122 in which a plurality of long slots 121 are formed, and supporting surfaces 130a and 130b for supporting the tension mask 122. And first and second support members 123a and 123b spaced at predetermined intervals. The first and second support members 123a and 123b have a "b" cross section and are arranged to be symmetrical.

First and second rigid members 124a and 124b disposed at predetermined intervals between the first and second support members 123a and 123b to support the first and second support members 123a and 123b. Is installed. The first and second rigid members 124a and 124b are arranged to connect lower ends of both ends of the first and second support members 123a and 123b.

In addition, first and second connection members 127a and 127b are formed to connect both ends of the first and second support members 123a and 123b. The first and second connection members 127a and 127b may be formed by a difference in thermal expansion between the first and second rigid members 124a and 124b and the first and second support members 123a and 123b. First and second support members 123a and 123b and the tension mask 122 serve to correct mis-landing of the electron beam due to the thermal bottle of the tension mask 122 and the frame 150 by changing the curvature in the tube axis direction. .

Meanwhile, the frame 150 on which the tension mask 122 is mounted is suspended on the inner surface of the panel. For this purpose, the frame 150 may be coupled to stud pins (not shown) installed on the inner surface of the panel. The four hook units 151, 152, 153 and 154 are provided, and the first, second, third and fourth hook units 151, 152, 153 and 154 are respectively spring supporters 151a ( 152a, 153a, 154a, and springs 151b, 152b, 153b, 154b coupled with the spring supporters 151a, 152a, 153a, 154a.

Each of the spring supporters 151a and 152a of the first and second hook units 151 and 152 extends downwardly with respect to the first and second support members 123a and 123b so that the free ends of the first and second hook units 151 and 152 extend. The spring supporters 153a and 154a of the third and fourth hook units 153 and 154 are fixed by welding so that they are positioned below the support members 123a and 123b. It extends upward with respect to the members 124a and 124b and is fixed by welding so that the free end is positioned above the first and second rigid members 124a and 124b. Springs 151b, 152b, 153b and 154b are coupled to the spring supporters 151a, 152a, 153a and 154a, respectively, and each of the springs 151b, 152b, 153b and 154b. The coupling holes 151c, 152c, 153c, and 154c, which can be coupled to the stud pins of the panel, are formed, and the coupling holes 151c, 152c, 153c, and 154c are approximately first and second. The support members 123a and 123b and the first and second rigid members 124a and 124b are positioned to correspond to the centers. Accordingly, the spring supporters 151a, 152a, 153a, and 154a are formed from the centers of the first and second support members 123a and 123b and the first and second rigid members 124a and 124b, respectively. It will be welded out of a certain distance.

However, in order to minimize the effects of the overall thermal drift, it is necessary to manufacture the tension mask frame 150 so that the effects of thermal expansion and the saddle doming cancel each other out. That is, since thermal drift due to thermal expansion has a negative value and thermal drift due to saddle domining has a positive value, the tension mask frame assembly 100 must be manufactured so that they are offset.

However, since it is difficult to control the thermal drift by thermal expansion, the influence of the thermal drift should be reduced by changing the saddle domming. The portion close to the end should be designed for the tension mask frame 150 to increase the amount of off.

5A illustrates the first support member 123a of the frame 150 in FIG. 3 taken along the F direction, and FIG. 5B illustrates the second support member 123b of the frame 150 in FIG. 3 in the G direction. It is a figure shown in figure.

Referring to FIG. 5A, a curved line having a plurality of radii of curvature is formed between both ends d1 and e1 of the first supporting surface 130a of the first supporting member 123a on which the tension mask 100 is mounted. . In the tension mask frame assembly 100 for a color cathode ray tube according to the present invention, the radius of curvature of the longitudinal direction of the first ground surface 130a is close to the distance x1 from the center a1 of the first ground surface 130a. The distance x1 from is formed to be greater than or equal to the longitudinal radius of curvature of the first support surface 130a.

In the present embodiment, the longitudinal curvature radius R11 of the support surface 130a between the eleventh inflection point b1 and the twelfth inflection point c1 is between the eleventh inflection point b1 and one end d1 or the twelfth. It is larger than the longitudinal curvature radius R12 (R13) of the first supporting surface 130a between the inflection point c1 and the other end e1. Therefore, the radius of curvature of the first supporting surface 130a changes with the eleventh inflection point b1 and the twelfth inflection point c1 before and after.

In addition, the radius of curvature of the first support surface 130a is preferably symmetrical with respect to the longitudinal center a1 of the first support surface 130a. Therefore, the radius of curvature R12 between the eleventh inflection point b1 and the one end d1 is the same as the other longitudinal curvature radius R13.

In the case of the second support member 123b shown in FIG. 5B, similar to the first support member 123a of FIG. 4A, the distance x2 from the center a2 of the second support surface 130b is close to the first support member 123a. The longitudinal radius of curvature of the second ground surface 130b is formed to be greater than or equal to the longitudinal radius of curvature of the second ground surface 130b far from the center a2.

In the present embodiment, the radius of curvature R21 of the second support surface 130b between the twenty-first inflection point b2 and the twenty-second inflection point c2 is between the twenty-first inflection point b2 and the one end d2, or It is larger than the longitudinal curvature radius R22 (R23) of the second supporting surface 130b between the 22nd inflection point c2 and the other end e2.

In addition, the radius of curvature of the second support surface 130b is preferably symmetrical with respect to the longitudinal center a2 of the second support surface 130b. Therefore, the longitudinal curvature radius R22 between the twenty-first inflection point b2 and the one end d2 is the same as the other longitudinal curvature radius R23.

It is preferable for the balance of the frame 150 that the radii of curvature of the first and second supporting surfaces 130a and 130b of the first and second supporting members 123a and 123b are symmetric with each other.

6 illustrates the tension mask 122 seated on the tension mask frame 150 according to an embodiment of the present invention, and the tension mask frame according to the related art with respect to the amount of turning off the tension mask 122 by saddle doming. This is a graph comparing the amount of off of the tension mask. The horizontal axis of the graph represents the position from the center of the tension mask to the horizontal direction, and the vertical axis represents the center off amount.

As shown, compared to the tension mask seated on the tension mask frame according to the prior art, the amount of off of the tension mask 122 seated on the tension mask frame 150 according to the present invention is relatively increased. In the tension mask 122 seated on the tension mask frame 150 according to the present invention, the amount of off of the tension mask 122 is the largest at the horizontal centers a1 and a2 of the tension mask 122, and from the center. It can be seen that the amount of off of the tension mask 122 decreases as the distance increases. In particular, since the curvature radii R12, R13, R22 and R23 of the supporting members 123a and 123b are reduced from the inflection points b1, c1, b2 and c2, the center of this part is reduced. It can be seen that there is an inflection point in the off amount.

When the amount of off in the tension mask is increased, thermal drift is increased by thermal expansion when the color cathode ray tube equipped with the tension mask is operated. As mentioned above, the thermal draft by saddle doming is opposite in direction to the thermal drift due to thermal expansion itself. That is, as opposed to the occurrence of thermal drift in the positive direction by saddle doming, the direction of the thermal drift due to thermal expansion itself is the negative direction.

However, in the tension mask assembly 100 for a color cathode ray tube according to an embodiment of the present invention, the inflection points (b1) (c1) (b2) (c2) and the ends (d1) (e1) (d2) (e2) Since the amount of off increases in between, the thermal drift in the positive direction by saddle domining at the inflection points b1 (c1) (b2) (c2) is increased. Therefore, the thermal drift by saddle doming cancels the thermal drift in the negative direction due to thermal expansion, so that the overall thermal drift is reduced.

Table 1 shows the thermal drift of the tension mask in the tension mask frame assemblies for the color cathode ray tube according to the prior art and an embodiment of the present invention.

Comparison of thermal drift of tension mask Prior art The present invention Position (mm) 150 300 320 150 300 320 Thermal Drift (mm) -17 19 25 -16 12 13

Referring to Table 1, in the tension mask frame assembly 100 according to an embodiment of the present invention, the absolute value of the thermal drift of the tension mask 122 is reduced as a whole. This is because the longitudinal curvature radius of the support surfaces 130a and 130b is reduced after the inflection points b1, c1, b2 and c2, so that the amount of off due to saddle doming is increased and the overall thermal drift is reduced. . Therefore, in the tension mask frame assembly for color cathode ray tubes according to the present invention, the change in landing due to thermal drift is reduced.

Like reference numerals in the drawings shown above indicate the same members.

The tension mask frame assembly for a color cathode ray tube according to the present invention has the following effects.

First, because the radius of curvature of the frame is not the single radius of curvature, but the radius of curvature of the support surface near the longitudinal center of the frame is greater than or equal to the radius of curvature of the support surface away from the center, thermal expansion by thermal drift by saddle doming. Thermal drift by is canceled out. Thus, the effect of the overall thermal drift is reduced.

Second, when the radius of curvature of the frame becomes symmetrical, structural stability is increased.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a perspective view showing a color cathode ray tube according to the prior art,

Figure 2 is a perspective view showing a tension mask frame assembly for a color cathode ray tube according to the prior art,

3 is a graph showing thermal drift by thermal expansion and saddle doming,

Figure 4 is an exploded perspective view of the tension mask frame assembly for a color cathode ray tube according to an embodiment of the present invention,

Figure 5a is a view showing a first support member taken in the direction F of Figure 4,

5B is a view showing a second support member taken in the G direction of FIG. 4,

6 is a graph showing the center off amount of the tension mask in the tension mask frame assembly for a color cathode ray tube.

Explanation of symbols on main parts of drawing

100: tension mask frame assembly for color cathode ray tube

122: tension masks 123a and 123b: first and second support members

124a, 124b: first and second rigid members 127a, 127b: first and second connecting members

130a, 130b: first and second ground 150: frame

b1: 11th inflection point c1: 12th inflection point

b2: 21st inflection point c2: 22nd inflection point

Claims (4)

Tension mask; First and second support members spaced at predetermined intervals and including first and second support surfaces on which the tension mask is seated; First and second connection members spaced apart at predetermined intervals between the first and second support members and connecting the first and second support members; And A first and second rigid members disposed between the first and second support members and supporting the first and second support members, The longitudinal radius of curvature of the first edge portion close to the longitudinal center of the first edge is greater than or equal to the radius of curvature of the longitudinal portion of the first edge portion away from the center; Tension mask frame for color cathode ray tube, characterized in that the longitudinal radius of curvature of the second ground portion near the longitudinal center of the second ground surface is greater than or equal to the radius of curvature of the second ground portion away from the center. Assembly. The tension mask frame assembly for color cathode ray tubes according to claim 1, wherein the longitudinal curvature radii of the first and second supporting surfaces are symmetrical with respect to the centers, respectively. The method of claim 1, wherein the eleventh and twelfth inflection points are respectively located on the first ground plane to be symmetrical with respect to the longitudinal center of the first ground plane The support surface between the eleventh inflection point and the twelfth inflection point has a longitudinal radius of curvature R11, The support surfaces between the longitudinal ends of the first supporting ground and the inflection points adjacent to the longitudinal ends of the first supporting ground respectively have a longitudinal radius of curvature R12, Tension mask frame assembly for color cathode ray tube, characterized in that R11≥R12. According to claim 1, wherein the twenty-first and twenty-second inflection points are respectively located on the second ground surface to be symmetrical to the longitudinal center of the second ground surface The support surface between the twenty-first inflection point and the twenty-second inflection point has a longitudinal radius of curvature R21, The supporting surfaces between the longitudinal ends of the second supporting ground and the inflection points adjacent to the longitudinal ends of the second supporting ground respectively have a longitudinal radius of curvature R22, Tension mask frame assembly for color cathode ray tube, characterized in that R21≥R22.